Risk-adjusted rates between hospitals for adverse outcomes of very-low-birth-weight infants

Risk Factors for Mortality or Major Morbidities of Very Preterm Infants: A Study from Thailand

OBJECTIVE

Very preterm neonates have high rates of composite outcomes featuring mortality and major morbidities. If the modifiable risk factors could be identified, perhaps the rates could be decreased especially in resource-limited settings.

STUDY DESIGN

We performed a prospective study in a Thai neonatal intensive care unit to identify the risk factors of composite outcomes between 2014 and 2021. The inclusion criterion was neonates who were born in our hospital at a gestational age (GA) of less than 32 weeks. The exclusion criteria were neonates who died in the delivery room or had major congenital anomalies. The composite outcomes were analyzed by multivariable logistic regression with adjusted odds ratios (aORs) and a 95% confidence interval (CI).

RESULTS

Over the 8-year study period, 555 very preterm inborn neonates without major birth defects were delivered. The composite outcomes were 29.4% (163/555). The medians (interquartile ranges) of GA and birth weights of the neonates were 29 (27-31) weeks and 1,180 (860-1,475) grams, respectively. By multivariable analysis, GA (aOR: 0.65; 95% CI: 0.55-0.77), small for GA (aOR: 4.93; 95% CI: 1.79-13.58), multifetal gestation (aOR: 2.23; 95% CI: 1.12-4.46), intubation within 24 hours (aOR: 5.39; 95% CI: 1.35-21.64), and severe respiratory distress syndrome (aOR: 5.00; 95% CI: 1.05-23.89) were significantly associated with composite outcomes.

CONCLUSION

Very preterm infants who had a lower GA were small for GA, twins or more, respiratory failure on the first day of life, and severe respiratory distress syndrome were associated with mortality and/or major morbidities.

KEY POINTS

· In very preterm neonates, the composite outcomes and mortality rate were 29.4 and 12.3%.. · Composite outcomes were associated with lower GA, SGA, multifetal gestation, intubation, and severe RDS.. · Mortality was associated with lower GA or Apgar score at 5 minutes, SGA, and PPHN..

Interferon-stimulated gene 15 polymorphisms are associated with spontaneous preterm birth in Taiwanese women

PROBLEM

Immune and inflammatory responses are known to be major causes of preterm birth (PTB). The maternal genetic background plays an important role in the development of PTB. Interferon-stimulated gene 15 (ISG15) is an interferon-induced protein which can modulate immune cell activation and function. We aim to study if polymorphisms in the ISG15 gene are associated with spontaneous PTB (sPTB) risk in Taiwanese women.

METHOD OF STUDY

ISG15 rs4615788 C/G, rs1921 G/A, and rs8997 A/G polymorphisms were genotyped in a hospital-based study of 112 women with sPTB and 1120 term controls. The plasma concentrations of ISG15 were determined by enzyme-linked immunosorbent assay.

RESULTS

We found the ISG15 rs1921 G-rs8997 A haplotype was associated with decreased risk for PTB (χ2  = 6.26, p = .01, pc  = .04). The A/G genotype of ISG15 rs8997 polymorphism might have the potential to confer reduced risk of PTB women (χ2  = 4.09, p = .04, pc  = .08). Spontaneous PTB women displayed higher plasma ISG15 levels compared to term controls (p < .001). The plasma ISG15 levels among pregnant women with rs8997 A/G genotype were found significantly lower compared to G/G genotype (p = .03).

CONCLUSIONS

Women with the ISG15 rs1921 G-rs8997 A haplotype may associate with spontaneous PTB. These findings provide new insights into the etiology of preterm birth.

The effect of patient volume on mortality and morbidity of extremely low birth weight infants in Taiwan

BACKGROUND

To assess whether the number of extremely low birth weight (ELBW) infants treated annually in neonatal intensive care units (NICUs) in Taiwan affects the mortality and morbidity of this patient population.

METHODS

This retrospective cohort study included preterm infants with ELBW (≤1000 g). NICUs were divided into three subgroups according to the annual admissions of ELBW infants (low, ≤10; medium, 11-25; and high, >25). Perinatal characteristics, mortality, and short-term morbidities were compared between groups.

RESULTS

A total of 1945 ELBW infants from 17 NICUs were analyzed (low-volume, n = 263; medium-volume, n = 420; and high-volume, n = 1262). After risk adjustments, infants from NICUs with low patient volumes were at a higher risk of death. The risk-adjusted odds ratios (aOR) for mortality were 0.61 (95% CI, 0.43-0.86) in the high-volume NICUs and 0.65 (95% CI, 0.43-0.98) in medium-volume NICUs, compared with infants admitted to low-volume NICUs. Infants in medium-volume NICUs had the lowest incidence of prenatal steroid exposure (58.1%, P < 0.001) and were associated with the highest risk of necrotizing enterocolitis (aOR, 2.35 [95% CI, 1.48-3.72]), severe intraventricular hemorrhage (aOR, 1.55 [95% CI, 1.01-2.28]), and bronchopulmonary dysplasia (aOR, 1.61 [95% CI, 1.10-2.35]). However, survival without major morbidity did not differ between the groups.

CONCLUSION

The mortality risk was higher among ELBW infants admitted to NICUs with a low annual patient volume. This may emphasize the importance of systematically referring patients from these vulnerable populations to appropriate care settings.